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81.

Purpose

To test the effectiveness of a central venous catheter (CVC) insertion strategy and a hand hygiene (HH) improvement strategy to prevent central venous catheter-related bloodstream infections (CRBSI) in European intensive care units (ICUs), measuring both process and outcome indicators.

Methods

Adult ICUs from 14 hospitals in 11 European countries participated in this stepped-wedge cluster randomised controlled multicentre intervention study. After a 6 month baseline, three hospitals were randomised to one of three interventions every quarter: (1) CVC insertion strategy (CVCi); (2) HH promotion strategy (HHi); and (3) both interventions combined (COMBi). Primary outcome was prospective CRBSI incidence density. Secondary outcomes were a CVC insertion score and HH compliance.

Results

Overall 25,348 patients with 35,831 CVCs were included. CRBSI incidence density decreased from 2.4/1000 CVC-days at baseline to 0.9/1000 (p < 0.0001). When adjusted for patient and CVC characteristics all three interventions significantly reduced CRBSI incidence density. When additionally adjusted for the baseline decreasing trend, the HHi and COMBi arms were still effective. CVC insertion scores and HH compliance increased significantly with all three interventions.

Conclusions

This study demonstrates that multimodal prevention strategies aiming at improving CVC insertion practice and HH reduce CRBSI in diverse European ICUs. Compliance explained CRBSI reduction and future quality improvement studies should encourage measuring process indicators.
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83.
Human papillomaviruses (HPVs) are the causative agents of benign and malignant lesions of the epithelium. Despite their high prevalence, there is currently no antiviral drug for the treatment of HPV-induced lesions. The ATPase and helicase activities of the highly conserved E1 protein of HPV are essential for viral DNA replication and pathogenesis and hence are considered valid antiviral targets. We recently described novel biphenylsulfonacetic acid inhibitors of the ATPase activity of E1 from HPV type 6 (HPV6). Based on kinetics and mutagenesis studies, we now report that these compounds act by an allosteric mechanism. They are hyperbolic competitive inhibitors of the ATPase activity of HPV6 E1 and also inhibit its helicase activity. Compounds in this series can also inhibit the ATPase activity of the closely related enzyme from HPV11; however, the most potent inhibitors of HPV6 E1 are significantly less active against the type 11 protein. We identified a single critical residue in HPV6 E1, Tyr-486, substituted by a cysteine in HPV11, which is primarily responsible for this difference in inhibitor potency. Interestingly, HPV18 E1, which also has a tyrosine at this position, could be inhibited by biphenylsulfonacetic acid derivatives, thereby raising the possibility that this class of inhibitors could be optimized as antiviral agents against multiple HPV types. These studies implicate Tyr-486 as a key residue for inhibitor binding and define an allosteric pocket on HPV E1 that can be exploited for future drug discovery efforts.  相似文献   
84.
Microsporidia of the genus Encephalitozoon are increasingly being reported as a cause of severe, often disseminated infections, mainly in patients with acquired immunodeficiency syndrome (AIDS). Immunological identification of each of the three recognized species (E. cuniculi, E. hellem, and E. intestinalis) requires the availability of specific immune sera. All sera available thus far have been generated by direct inoculation of rabbits with virulent microsporidian spores. This study demonstrates for the first time that subcutaneous immunization with inactivated spores of E. cuniculi, E. hellem, or E. intestinalis is capable of generating highly active rabbit hyperimmune sera to the homologous antigens, with maximal titers being 1:5,120, 1:1,280, and 1:2,560, respectively, as determined by the indirect immunofluorescence technique (IIF). Broad cross-reactivity of the rabbit antisera with all heterologous Encephalitozoon antigens was determined by IIF and immunogold electron microscopy; however, only the E. hellem immune serum strongly cross-reacted with spores of Enterocytozoon bieneusi. During the 35-month follow-up period the antibody titers to the homologous antigens declined to 1:640, 1:160, and 1:320, respectively. The observed decay curves for antibody titers against E. cuniculi, E. hellem, and E. intestinalis were fitted using mathematical modeling, resulting in a predicted duration for specific immune responses of about 7 years on average. Knowledge of the magnitude and duration of specific immune responses is a prerequisite for further evaluation of the concept of using inactivated microsporidian spores in the quest for vaccines against microsporidian infections. Received: 10 April 2000 / Accepted: 18 July 2000  相似文献   
85.
86.
From 1996 to 2002, hepatitis C virus (HCV) typing was prospectively performed for 1,281 unselected HCV-infected and viremic patients, irrespective of their clinical status. Eighty-three patients (6.5%) were coinfected with human immunodeficiency virus (HIV) and HCV. A total of 1,195 strains were identified by a serotype screening (Murex HCV Serotyping 1-6 assay) and/or genotyping (Inno-LiPA HCV II) test. The distribution of HCV types showed an unusually high rate of type 5 (14.2%) that was stable over time and was the third most frequent type, after type 1 (59.1%) and type 3 (15.1%). HCV type 5 was more frequent in patients who were older than 50 (P = 10(-6)), but its frequency did not differ significantly by gender (P = 0.21). Serotyping was performed for 1,160 strains but failed for 30.2% of them. The efficiency depended on HIV status (for HCV-HIV-coinfected patients, half of the strains were untypeable) and HCV type. Genotyping was performed for 428 samples, with an overall efficiency of 99.3%. It failed in three cases, which were subsequently identified as HCV type 2. Serotyping and genotyping results for 39 patients showed discrepancies between the two methods for 4 patients, who had HCV type 2, type 6, or mixed infections. Thus, HCV type 5 may also be encountered frequently in Western countries. Its apparent confinement to a restricted area raises the question of how it emerged and underscores the need for further studies of HCV type prevalence, routes of transmission, pathogenicity, and responses to treatment.  相似文献   
87.
Specific inhalation challenge can help differentiate occupational asthma from allergic alveolitis caused by malt.  相似文献   
88.
Aspiration biopsy by fine needle from the major salivary glands has been studied. To evaluate this form of biopsy, 34 patients with salivary gland enlargement were examined. By this technic, 29 has confirmative histology. The method proved complication free and accurate. The safety of this biopsy form has been proven. The accuracy of this method may be high, particularly, for the most common benign mixed tumor. Thus this procedure is suggested for initial examination of all lesions of the salivary gland.  相似文献   
89.
A child presented in early childhood with episodes of coma and hypoglycemia and a rapidly evolutive myopathy and cardiomyopathy leading to death at 9 mo of age. Ketosis was decreased (blood beta-hydroxybutyrate: 0.07 mmol/L) despite normal plasma levels of fatty acids (0.81 mmol/L). The patient's urine contained excessive amounts of the C6 to C10 dicarboxylic acids present in almost all defects of fatty acid mitochondrial oxidation. More specifically, gas chromatography-mass spectrometry identified an accumulation of medium- and long-chain (C8 to C14) 3-hydroxy-dicarboxylic acids, suggesting a defect of the mitochondrial enzyme that normally dehydrogenates these 3-hydroxyacyl-CoA esters. Biochemical studies in the patient's cultured fibroblasts confirmed the impairment of medium- and long-chain fatty acid oxidation, and allowed the recognition of the deficiency of long-chain 3-hydroxyacyl-CoA dehydrogenase. The activities of long-, medium-, and short-chain acyl-CoA dehydrogenases and 3-ketoacyl-CoA thiolase were normal. These results describe a disorder of fatty acid metabolism that affects the liver, skeletal muscles, and myocardium. It is important to point out that long-chain 3-hydroxyacyl-CoA deficiency shares many clinical similarities with systemic carnitine deficiency, as well as with carnitine-palmityl-CoA transferase and long-chain acyl-CoA dehydrogenase deficiencies. The differential diagnosis of this disease relies on the demonstration of long-chain urinary dicarboxylic acids with a hydroxyl group in 3-position and the study of the enzyme activity in cultured fibroblasts.  相似文献   
90.
We describe the clinical and laboratory features in three Caucasian Chilean patients with tropical spastic paraparesis (TSP) associated with/or preceded by a lymphoproliferative disorder involving cutaneous lesions and localised lymphadenopathy. The neurological symptoms and signs were characteristic of TSP and CSF examination revealed the presence of oligoclonal bands. All three patients had a moderate leucocytosis (10-14 × 109/1) with eosinophilia and a minority (2-4%) of circulating atypical polylobed or ATLL-like lymphocytes. Lymph node histology showed a diffuse pattern of infiltration (1 case) and marked expansion of the paracortical zone with convoluted lymphocytes and immunoblasts (2 cases). Skin biopsy demonstrated a dermal lymphoid infiltration with epidermotropism. Antibodies to HTLV-I were detected in the serum and CSF in the three patients and Southern blot analysis of peripheral blood mononuclear cells showed a monoclonal integration of HTLV-I proviral DNA in one case whereas in the two others the pattern was indicative of low level polyclonal integration. All three patients were treated with prednisolone and one with PUVA with transient partial response on the skin and neurological manifestations. Two patients died months to 5 years from presentation and the other is alive 12 years from diagnosis with active neurological and skin disease. The simultaneous occurrence of HTLV-I associated TSP with smouldering ATLL and a cutaneous ATLL or pre-leukaemic form is discussed.  相似文献   
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